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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
Hideo Hirayama
Nuclear Technology | Volume 77 | Number 1 | April 1987 | Pages 60-67
Technical Paper | Radioisotopes and Isotope Separation | doi.org/10.13182/NT87-A33952
Articles are hosted by Taylor and Francis Online.
Exposure buildup factors for plane normal sources have been calculated with an electron gamma shower Monte Carlo code, EGS4, for water, concrete, iron, and lead in the 10 to 100 MeV range. Electron reactions like multiple scattering, collision, and continuous energy loss are taken into account together with bremsstrahlung. The buildup factors in this energy region are affected very much by the energy loss mechanism of electrons and positrons in the medium. The energy of electrons or positrons in lead is mainly converted to photons via the bremsstrahlung reaction; therefore, buildup factors increase rapidly with the increase of the photon energy. In the case of water, the energy of electrons or positrons is mainly spent in ionization or excitation. Buildup factors for water decrease gradually to 40 MeV and increase gradually above that energy. The buildup factors in each medium are calculated for eight-source energy from 10 to 100 MeV for penetration depths as great as 10 mfp.